矿床地质2011，Vol.30Issue(2)：327-338,12.
西藏谢通门县雄村斑岩型铜金矿集区Ⅰ号矿体的蚀变与矿化特征
Alteration and mineralization of No.Ⅰ ore body in Xiongcun porphyry copper-gold metallogenic ore district, Xietongmen County, Tibet
摘要
Abstract
The Xiongcun porphyry copper-gold metallogenic district, located in the Gangdise metallogenic belt, is the only copper-gold metallogenic ore district related to early subduction activity of Neotethys oceanic crust.It iscomposed of No.Ⅰ , No.Ⅱ and No.Ⅲ ore bodies.In this paper, the Xiongcun No.Ⅰ ore body was chosen asthe research object.This ore body has the characteristics of large size, strong alteration, poor molybdenite and rich gold.The alteration-mineralization system is controlled by several middle-late Jurassic quartz diorite porphyry with big quartz eyes which intruded into tuff of Xiongcun Formation.The Xiongcun No.Ⅰ ore body liesin the quartz diorite porphyry with big quartz eyes and the tuff.Based on a study of its alteration and mineralization, the authors have reached the following conclusions: ① The alteration of the Xiongcun No.Ⅰ ore body occurred at two stages (early stage and late stage).The early stage included poorly developed potassic alterationand well developed andalusite-silicification, whereas the late stage included phyllic alteration and propylitic alteration, with the late stage superimposed upon the early stage.From the core of the porphyry, the alteration zoning is in order of strong silicification zone → andalusite-silicification zone → phyllic zone → propylitic zone.The main mineralization zone is composed of strong silicification zone and andalusite-silicification zone.② Mineralization of the Xiongcun No.Ⅰ ore body find expression in dissemination-veins or stockworks.From the core of the porphyry, the mineralization zoning is in order of pyrite-chalcopyrite-(pyrrhotite)→pyrite-pyrrhotite-(chalcopyrite)→pyrite→sphalerite, and the mineralization veins zoning is in order of quartz-sulfide vein→quartz-andalusite-biotite± muscovite-sulfide veinp→yrite vein→polymetallic sulfide vein.The main mineralization veins are quartz-sulfide vein and quartz-andalusite-biotite ± muscovite-sulfide vein.After the formation of the ore deposit, it experienced weak supergenic alteration and formed the oxidized zone and supergene sulfide zone, but the main ore body is located in the hypogene sulfide zone.③ The presence of poorly-developed potassic alteration and well developed andalusite-silicification alteration implies that the fluids were characterized by relatively low K+/H- ratio and experienced a period of high temperature and formed poorly-developed potassic alteration, and then the fluids entered into a stage of slightly lower temperature and formed well developed andalusite silicification.The lower temperature might have resulted from the involvement of cooler meteoric waters in the alteration system.关键词
地质学/雄村/斑岩型铜金矿床/蚀变/矿化/红柱石Key words
geology/ Xiongcun/ porphyry copper-gold deposit/ alteration/ mineralization/ andalusite分类
天文与地球科学引用本文复制引用
郎兴海,唐菊兴,李志军,黄勇,陈渊,张丽..西藏谢通门县雄村斑岩型铜金矿集区Ⅰ号矿体的蚀变与矿化特征[J].矿床地质,2011,30(2):327-338,12.基金项目
本文为国家科技支撑项目(编号:2006BAB01A01)、天圆公司项目、青藏专项(编号:1212010818089)、国家基础研究计划"印度-亚洲大陆主碰撞带成矿作用"973项目(编号:2002CB412607)资助的成果 （编号:2006BAB01A01）
